The title is pretty much self-explanatory - oh UEFI. "You can read more of what is known at H-Online, but the short summary is this: Samsung's UEFI implementation appears to be faulty. It was most likely tested with Windows only and found to work, but thorough testing with other operating systems doesn't appear to have been a priority - or perhaps a consideration at all. At present, the bug appears to affect Samsung 530U3C, 300E5C, NP700Z5C, NP700Z7C, and NP900X4C series laptops; if you have one of those laptops, we recommend you exercise extreme caution if you have a need to boot into a Linux environment."